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	/*
	* Copyright (c) 1994, 2017, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.lang;

	import jdk.internal.HotSpotIntrinsicCandidate;

	/**
	* Class {@code Object} is the root of the class hierarchy.
	* Every class has {@code Object} as a superclass. All objects,
	* including arrays, implement the methods of this class.
	*
	* @author unascribed
	* @see java.lang.Class
	* @since 1.0
	*/
	public class Object {

	private static native void registerNatives();
	static {
	registerNatives();
	}

	/**
	* Constructs a new object.
	*/
	@HotSpotIntrinsicCandidate
	public Object() {}

	/**
	* Returns the runtime class of this {@code Object}. The returned
	* {@code Class} object is the object that is locked by {@code
	* static synchronized} methods of the represented class.
	*
	* <p><b>The actual result type is {@code Class<? extends \|X\|>}
	* where {@code \|X\|} is the erasure of the static type of the
	* expression on which {@code getClass} is called.</b> For
	* example, no cast is required in this code fragment:</p>
	*
	* <p>
	* {@code Number n = 0; }<br>
	* {@code Class<? extends Number> c = n.getClass(); }
	* </p>
	*
	* @return The {@code Class} object that represents the runtime
	* class of this object.
	* @jls 15.8.2 Class Literals
	*/
	@HotSpotIntrinsicCandidate
	public final native Class<?> getClass();

	/**
	* Returns a hash code value for the object. This method is
	* supported for the benefit of hash tables such as those provided by
	* {@link java.util.HashMap}.
	* <p>
	* The general contract of {@code hashCode} is:
	* <ul>
	* <li>Whenever it is invoked on the same object more than once during
	* an execution of a Java application, the {@code hashCode} method
	* must consistently return the same integer, provided no information
	* used in {@code equals} comparisons on the object is modified.
	* This integer need not remain consistent from one execution of an
	* application to another execution of the same application.
	* <li>If two objects are equal according to the {@code equals(Object)}
	* method, then calling the {@code hashCode} method on each of
	* the two objects must produce the same integer result.
	* <li>It is <em>not</em> required that if two objects are unequal
	* according to the {@link java.lang.Object#equals(java.lang.Object)}
	* method, then calling the {@code hashCode} method on each of the
	* two objects must produce distinct integer results. However, the
	* programmer should be aware that producing distinct integer results
	* for unequal objects may improve the performance of hash tables.
	* </ul>
	* <p>
	* As much as is reasonably practical, the hashCode method defined
	* by class {@code Object} does return distinct integers for
	* distinct objects. (The hashCode may or may not be implemented
	* as some function of an object's memory address at some point
	* in time.)
	*
	* @return a hash code value for this object.
	* @see java.lang.Object#equals(java.lang.Object)
	* @see java.lang.System#identityHashCode
	*/
	@HotSpotIntrinsicCandidate
	public native int hashCode();

	/**
	* Indicates whether some other object is "equal to" this one.
	* <p>
	* The {@code equals} method implements an equivalence relation
	* on non-null object references:
	* <ul>
	* <li>It is <i>reflexive</i>: for any non-null reference value
	* {@code x}, {@code x.equals(x)} should return
	* {@code true}.
	* <li>It is <i>symmetric</i>: for any non-null reference values
	* {@code x} and {@code y}, {@code x.equals(y)}
	* should return {@code true} if and only if
	* {@code y.equals(x)} returns {@code true}.
	* <li>It is <i>transitive</i>: for any non-null reference values
	* {@code x}, {@code y}, and {@code z}, if
	* {@code x.equals(y)} returns {@code true} and
	* {@code y.equals(z)} returns {@code true}, then
	* {@code x.equals(z)} should return {@code true}.
	* <li>It is <i>consistent</i>: for any non-null reference values
	* {@code x} and {@code y}, multiple invocations of
	* {@code x.equals(y)} consistently return {@code true}
	* or consistently return {@code false}, provided no
	* information used in {@code equals} comparisons on the
	* objects is modified.
	* <li>For any non-null reference value {@code x},
	* {@code x.equals(null)} should return {@code false}.
	* </ul>
	* <p>
	* The {@code equals} method for class {@code Object} implements
	* the most discriminating possible equivalence relation on objects;
	* that is, for any non-null reference values {@code x} and
	* {@code y}, this method returns {@code true} if and only
	* if {@code x} and {@code y} refer to the same object
	* ({@code x == y} has the value {@code true}).
	* <p>
	* Note that it is generally necessary to override the {@code hashCode}
	* method whenever this method is overridden, so as to maintain the
	* general contract for the {@code hashCode} method, which states
	* that equal objects must have equal hash codes.
	*
	* @param obj the reference object with which to compare.
	* @return {@code true} if this object is the same as the obj
	* argument; {@code false} otherwise.
	* @see #hashCode()
	* @see java.util.HashMap
	*/
	public boolean equals(Object obj) {
	return (this == obj);
	}

	/**
	* Creates and returns a copy of this object. The precise meaning
	* of "copy" may depend on the class of the object. The general
	* intent is that, for any object {@code x}, the expression:
	* <blockquote>
	* <pre>
	* x.clone() != x</pre></blockquote>
	* will be true, and that the expression:
	* <blockquote>
	* <pre>
	* x.clone().getClass() == x.getClass()</pre></blockquote>
	* will be {@code true}, but these are not absolute requirements.
	* While it is typically the case that:
	* <blockquote>
	* <pre>
	* x.clone().equals(x)</pre></blockquote>
	* will be {@code true}, this is not an absolute requirement.
	* <p>
	* By convention, the returned object should be obtained by calling
	* {@code super.clone}. If a class and all of its superclasses (except
	* {@code Object}) obey this convention, it will be the case that
	* {@code x.clone().getClass() == x.getClass()}.
	* <p>
	* By convention, the object returned by this method should be independent
	* of this object (which is being cloned). To achieve this independence,
	* it may be necessary to modify one or more fields of the object returned
	* by {@code super.clone} before returning it. Typically, this means
	* copying any mutable objects that comprise the internal "deep structure"
	* of the object being cloned and replacing the references to these
	* objects with references to the copies. If a class contains only
	* primitive fields or references to immutable objects, then it is usually
	* the case that no fields in the object returned by {@code super.clone}
	* need to be modified.
	* <p>
	* The method {@code clone} for class {@code Object} performs a
	* specific cloning operation. First, if the class of this object does
	* not implement the interface {@code Cloneable}, then a
	* {@code CloneNotSupportedException} is thrown. Note that all arrays
	* are considered to implement the interface {@code Cloneable} and that
	* the return type of the {@code clone} method of an array type {@code T[]}
	* is {@code T[]} where T is any reference or primitive type.
	* Otherwise, this method creates a new instance of the class of this
	* object and initializes all its fields with exactly the contents of
	* the corresponding fields of this object, as if by assignment; the
	* contents of the fields are not themselves cloned. Thus, this method
	* performs a "shallow copy" of this object, not a "deep copy" operation.
	* <p>
	* The class {@code Object} does not itself implement the interface
	* {@code Cloneable}, so calling the {@code clone} method on an object
	* whose class is {@code Object} will result in throwing an
	* exception at run time.
	*
	* @return a clone of this instance.
	* @throws CloneNotSupportedException if the object's class does not
	* support the {@code Cloneable} interface. Subclasses
	* that override the {@code clone} method can also
	* throw this exception to indicate that an instance cannot
	* be cloned.
	* @see java.lang.Cloneable
	*/
	@HotSpotIntrinsicCandidate
	protected native Object clone() throws CloneNotSupportedException;

	/**
	* Returns a string representation of the object. In general, the
	* {@code toString} method returns a string that
	* "textually represents" this object. The result should
	* be a concise but informative representation that is easy for a
	* person to read.
	* It is recommended that all subclasses override this method.
	* <p>
	* The {@code toString} method for class {@code Object}
	* returns a string consisting of the name of the class of which the
	* object is an instance, the at-sign character `{@code @}', and
	* the unsigned hexadecimal representation of the hash code of the
	* object. In other words, this method returns a string equal to the
	* value of:
	* <blockquote>
	* <pre>
	* getClass().getName() + '@' + Integer.toHexString(hashCode())
	* </pre></blockquote>
	*
	* @return a string representation of the object.
	*/
	public String toString() {
	return getClass().getName() + "@" + Integer.toHexString(hashCode());
	}

	/**
	* Wakes up a single thread that is waiting on this object's
	* monitor. If any threads are waiting on this object, one of them
	* is chosen to be awakened. The choice is arbitrary and occurs at
	* the discretion of the implementation. A thread waits on an object's
	* monitor by calling one of the {@code wait} methods.
	* <p>
	* The awakened thread will not be able to proceed until the current
	* thread relinquishes the lock on this object. The awakened thread will
	* compete in the usual manner with any other threads that might be
	* actively competing to synchronize on this object; for example, the
	* awakened thread enjoys no reliable privilege or disadvantage in being
	* the next thread to lock this object.
	* <p>
	* This method should only be called by a thread that is the owner
	* of this object's monitor. A thread becomes the owner of the
	* object's monitor in one of three ways:
	* <ul>
	* <li>By executing a synchronized instance method of that object.
	* <li>By executing the body of a {@code synchronized} statement
	* that synchronizes on the object.
	* <li>For objects of type {@code Class,} by executing a
	* synchronized static method of that class.
	* </ul>
	* <p>
	* Only one thread at a time can own an object's monitor.
	*
	* @throws IllegalMonitorStateException if the current thread is not
	* the owner of this object's monitor.
	* @see java.lang.Object#notifyAll()
	* @see java.lang.Object#wait()
	*/
	@HotSpotIntrinsicCandidate
	public final native void notify();

	/**
	* Wakes up all threads that are waiting on this object's monitor. A
	* thread waits on an object's monitor by calling one of the
	* {@code wait} methods.
	* <p>
	* The awakened threads will not be able to proceed until the current
	* thread relinquishes the lock on this object. The awakened threads
	* will compete in the usual manner with any other threads that might
	* be actively competing to synchronize on this object; for example,
	* the awakened threads enjoy no reliable privilege or disadvantage in
	* being the next thread to lock this object.
	* <p>
	* This method should only be called by a thread that is the owner
	* of this object's monitor. See the {@code notify} method for a
	* description of the ways in which a thread can become the owner of
	* a monitor.
	*
	* @throws IllegalMonitorStateException if the current thread is not
	* the owner of this object's monitor.
	* @see java.lang.Object#notify()
	* @see java.lang.Object#wait()
	*/
	@HotSpotIntrinsicCandidate
	public final native void notifyAll();

	/**
	* Causes the current thread to wait until it is awakened, typically
	* by being <em>notified</em> or <em>interrupted</em>.
	* <p>
	* In all respects, this method behaves as if {@code wait(0L, 0)}
	* had been called. See the specification of the {@link #wait(long, int)} method
	* for details.
	*
	* @throws IllegalMonitorStateException if the current thread is not
	* the owner of the object's monitor
	* @throws InterruptedException if any thread interrupted the current thread before or
	* while the current thread was waiting. The <em>interrupted status</em> of the
	* current thread is cleared when this exception is thrown.
	* @see #notify()
	* @see #notifyAll()
	* @see #wait(long)
	* @see #wait(long, int)
	*/
	public final void wait() throws InterruptedException {
	wait(0L);
	}

	/**
	* Causes the current thread to wait until it is awakened, typically
	* by being <em>notified</em> or <em>interrupted</em>, or until a
	* certain amount of real time has elapsed.
	* <p>
	* In all respects, this method behaves as if {@code wait(timeoutMillis, 0)}
	* had been called. See the specification of the {@link #wait(long, int)} method
	* for details.
	*
	* @param timeoutMillis the maximum time to wait, in milliseconds
	* @throws IllegalArgumentException if {@code timeoutMillis} is negative
	* @throws IllegalMonitorStateException if the current thread is not
	* the owner of the object's monitor
	* @throws InterruptedException if any thread interrupted the current thread before or
	* while the current thread was waiting. The <em>interrupted status</em> of the
	* current thread is cleared when this exception is thrown.
	* @see #notify()
	* @see #notifyAll()
	* @see #wait()
	* @see #wait(long, int)
	*/
	public final native void wait(long timeoutMillis) throws InterruptedException;

	/**
	* Causes the current thread to wait until it is awakened, typically
	* by being <em>notified</em> or <em>interrupted</em>, or until a
	* certain amount of real time has elapsed.
	* <p>
	* The current thread must own this object's monitor lock. See the
	* {@link #notify notify} method for a description of the ways in which
	* a thread can become the owner of a monitor lock.
	* <p>
	* This method causes the current thread (referred to here as <var>T</var>) to
	* place itself in the wait set for this object and then to relinquish any
	* and all synchronization claims on this object. Note that only the locks
	* on this object are relinquished; any other objects on which the current
	* thread may be synchronized remain locked while the thread waits.
	* <p>
	* Thread <var>T</var> then becomes disabled for thread scheduling purposes
	* and lies dormant until one of the following occurs:
	* <ul>
	* <li>Some other thread invokes the {@code notify} method for this
	* object and thread <var>T</var> happens to be arbitrarily chosen as
	* the thread to be awakened.
	* <li>Some other thread invokes the {@code notifyAll} method for this
	* object.
	* <li>Some other thread {@linkplain Thread#interrupt() interrupts}
	* thread <var>T</var>.
	* <li>The specified amount of real time has elapsed, more or less.
	* The amount of real time, in nanoseconds, is given by the expression
	* {@code 1000000 * timeoutMillis + nanos}. If {@code timeoutMillis} and {@code nanos}
	* are both zero, then real time is not taken into consideration and the
	* thread waits until awakened by one of the other causes.
	* <li>Thread <var>T</var> is awakened spuriously. (See below.)
	* </ul>
	* <p>
	* The thread <var>T</var> is then removed from the wait set for this
	* object and re-enabled for thread scheduling. It competes in the
	* usual manner with other threads for the right to synchronize on the
	* object; once it has regained control of the object, all its
	* synchronization claims on the object are restored to the status quo
	* ante - that is, to the situation as of the time that the {@code wait}
	* method was invoked. Thread <var>T</var> then returns from the
	* invocation of the {@code wait} method. Thus, on return from the
	* {@code wait} method, the synchronization state of the object and of
	* thread {@code T} is exactly as it was when the {@code wait} method
	* was invoked.
	* <p>
	* A thread can wake up without being notified, interrupted, or timing out, a
	* so-called <em>spurious wakeup</em>. While this will rarely occur in practice,
	* applications must guard against it by testing for the condition that should
	* have caused the thread to be awakened, and continuing to wait if the condition
	* is not satisfied. See the example below.
	* <p>
	* For more information on this topic, see section 14.2,
	* "Condition Queues," in Brian Goetz and others' <em>Java Concurrency
	* in Practice</em> (Addison-Wesley, 2006) or Item 69 in Joshua
	* Bloch's <em>Effective Java, Second Edition</em> (Addison-Wesley,
	* 2008).
	* <p>
	* If the current thread is {@linkplain java.lang.Thread#interrupt() interrupted}
	* by any thread before or while it is waiting, then an {@code InterruptedException}
	* is thrown. The <em>interrupted status</em> of the current thread is cleared when
	* this exception is thrown. This exception is not thrown until the lock status of
	* this object has been restored as described above.
	*
	* @apiNote
	* The recommended approach to waiting is to check the condition being awaited in
	* a {@code while} loop around the call to {@code wait}, as shown in the example
	* below. Among other things, this approach avoids problems that can be caused
	* by spurious wakeups.
	*
	* <pre>{@code
	* synchronized (obj) {
	* while (<condition does not hold> and <timeout not exceeded>) {
	* long timeoutMillis = ... ; // recompute timeout values
	* int nanos = ... ;
	* obj.wait(timeoutMillis, nanos);
	* }
	* ... // Perform action appropriate to condition or timeout
	* }
	* }</pre>
	*
	* @param timeoutMillis the maximum time to wait, in milliseconds
	* @param nanos additional time, in nanoseconds, in the range range 0-999999 inclusive
	* @throws IllegalArgumentException if {@code timeoutMillis} is negative,
	* or if the value of {@code nanos} is out of range
	* @throws IllegalMonitorStateException if the current thread is not
	* the owner of the object's monitor
	* @throws InterruptedException if any thread interrupted the current thread before or
	* while the current thread was waiting. The <em>interrupted status</em> of the
	* current thread is cleared when this exception is thrown.
	* @see #notify()
	* @see #notifyAll()
	* @see #wait()
	* @see #wait(long)
	*/
	public final void wait(long timeoutMillis, int nanos) throws InterruptedException {
	if (timeoutMillis < 0) {
	throw new IllegalArgumentException("timeoutMillis value is negative");
	}

	if (nanos < 0 \|\| nanos > 999999) {
	throw new IllegalArgumentException(
	"nanosecond timeout value out of range");
	}

	if (nanos > 0) {
	timeoutMillis++;
	}

	wait(timeoutMillis);
	}

	/**
	* Called by the garbage collector on an object when garbage collection
	* determines that there are no more references to the object.
	* A subclass overrides the {@code finalize} method to dispose of
	* system resources or to perform other cleanup.
	* <p>
	* The general contract of {@code finalize} is that it is invoked
	* if and when the Java™ virtual
	* machine has determined that there is no longer any
	* means by which this object can be accessed by any thread that has
	* not yet died, except as a result of an action taken by the
	* finalization of some other object or class which is ready to be
	* finalized. The {@code finalize} method may take any action, including
	* making this object available again to other threads; the usual purpose
	* of {@code finalize}, however, is to perform cleanup actions before
	* the object is irrevocably discarded. For example, the finalize method
	* for an object that represents an input/output connection might perform
	* explicit I/O transactions to break the connection before the object is
	* permanently discarded.
	* <p>
	* The {@code finalize} method of class {@code Object} performs no
	* special action; it simply returns normally. Subclasses of
	* {@code Object} may override this definition.
	* <p>
	* The Java programming language does not guarantee which thread will
	* invoke the {@code finalize} method for any given object. It is
	* guaranteed, however, that the thread that invokes finalize will not
	* be holding any user-visible synchronization locks when finalize is
	* invoked. If an uncaught exception is thrown by the finalize method,
	* the exception is ignored and finalization of that object terminates.
	* <p>
	* After the {@code finalize} method has been invoked for an object, no
	* further action is taken until the Java virtual machine has again
	* determined that there is no longer any means by which this object can
	* be accessed by any thread that has not yet died, including possible
	* actions by other objects or classes which are ready to be finalized,
	* at which point the object may be discarded.
	* <p>
	* The {@code finalize} method is never invoked more than once by a Java
	* virtual machine for any given object.
	* <p>
	* Any exception thrown by the {@code finalize} method causes
	* the finalization of this object to be halted, but is otherwise
	* ignored.
	*
	* @apiNote
	* Classes that embed non-heap resources have many options
	* for cleanup of those resources. The class must ensure that the
	* lifetime of each instance is longer than that of any resource it embeds.
	* {@link java.lang.ref.Reference#reachabilityFence} can be used to ensure that
	* objects remain reachable while resources embedded in the object are in use.
	* <p>
	* A subclass should avoid overriding the {@code finalize} method
	* unless the subclass embeds non-heap resources that must be cleaned up
	* before the instance is collected.
	* Finalizer invocations are not automatically chained, unlike constructors.
	* If a subclass overrides {@code finalize} it must invoke the superclass
	* finalizer explicitly.
	* To guard against exceptions prematurely terminating the finalize chain,
	* the subclass should use a {@code try-finally} block to ensure
	* {@code super.finalize()} is always invoked. For example,
	* <pre>{@code @Override
	* protected void finalize() throws Throwable {
	* try {
	* ... // cleanup subclass state
	* } finally {
	* super.finalize();
	* }
	* }
	* }</pre>
	*
	* @deprecated The finalization mechanism is inherently problematic.
	* Finalization can lead to performance issues, deadlocks, and hangs.
	* Errors in finalizers can lead to resource leaks; there is no way to cancel
	* finalization if it is no longer necessary; and no ordering is specified
	* among calls to {@code finalize} methods of different objects.
	* Furthermore, there are no guarantees regarding the timing of finalization.
	* The {@code finalize} method might be called on a finalizable object
	* only after an indefinite delay, if at all.
	*
	* Classes whose instances hold non-heap resources should provide a method
	* to enable explicit release of those resources, and they should also
	* implement {@link AutoCloseable} if appropriate.
	* The {@link java.lang.ref.Cleaner} and {@link java.lang.ref.PhantomReference}
	* provide more flexible and efficient ways to release resources when an object
	* becomes unreachable.
	*
	* @throws Throwable the {@code Exception} raised by this method
	* @see java.lang.ref.WeakReference
	* @see java.lang.ref.PhantomReference
	* @jls 12.6 Finalization of Class Instances
	*/
	@Deprecated(since="9")
	protected void finalize() throws Throwable { }
	}

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